Screen cleaning gun



Sept. 2, w41. c. A. Ricou SCREEN CLEANING GNN Filed oct. 9, 19:59

WWW,

ATTORN EYS WITN ESS reception of a projectile I6.

Patented sept.' 2, 194i' SCREEN CLEANING GUN Clarence A. Ricou, Shreveport, La., assigner to Petroleum Increase Corporation,. Carthage, Tex., a corporation of Texas Application October 9, 1939, Serial No. 298,725 t (cl. 16s-zo) Y 1 l Claim.

My invention relates to oil, gas wells and the like, and .includes among its objects and advantages the provision of an'improved screen or liner gun for such wells.

Well casing screens or liners become impaired through the accumulation of various materials which block. the fluid from entering lthe well or casing. Frequently such accumulations are high- `ly abrasive in their character and would cause considerable damage to the pumping equipment if they were not strained from the uid. Various types of screens have been employed to excludev such material from entry into the pumping system, but cleaning of the screens has entailed considerable work and expense.

Accordingly, an object of my invention is to 1 provide a gun designed to utilize explosive forces effective on a column of fluid for forcing the uid through 'the screen or liner to effectively remove accumulations thereon so as to increase the production of the well. In my invention, the fluid column reacted by the explosive forces constitutes a projectile which eiectively removes accumulationsfrom the well screen or liner.

In the accompanying drawing:

Figure 1 is an elevational view of a gun in accordance with my invention;

Figure 2 is a sectional view along the line 2-2 of Figure 1;

Figure 3 is a detail view of a go-devil which may be employed for ring the gun; and

Figure 4 is'a sectional detail view illustrating a line means which may be employed lfor lowering the gun into a well'in combination with a different form of iiring mechanism.

In the embodiment selected to illustrate my invention, the gun I comprises a cylindrical body I2, bored at I4 to provide a powder chamber, which bore terminates in a larger bore I6 for the Projectile I6 includes a cylindrical body 26 pressed into the projectile bore I6, and the projectile includes a tapered nose 22.

Between the shoulder 2.4 and the rear face of the projectile .I6 I position a lead plate 26 which constitutes a seal for the powder chamber I4.

-Coaxiallywith the projectile bore I6 I provide a larger bore 26 within which I position a lead washer 'i6 having a central opening iitting tightly against the tapered nose 22. Between a metal washer 32 and the lead washer 30 Iposition a copper gasket 34, with the iron ring and the gasket having central openings through which 66 is threaded intolthe bore 28, as at 36 for the application of pressure to the washers 36, 32 and 34 for the purpose of urging the projectile against the sealing plate 26. thus effectively anchoring the projectile in addition to providing an effective seal so as Vto prevent the entrance of moisture into the powder chamber.

A powder bore4 or train 40 establishes communi cation between the powder chamber I4 andthe lower part of a bore 42 extending inwardly ofthe upper end of the body I2. Bore 42 is internally threaded at 44 for the reception of a sleeve 46 having a wall 46 spaced slightly from the bottom of the bore 42 to provide a space 50 for powder or other suitable explosive material, which is also contained in the powder chamber I4 as well as the bore 46.

Wall 46 is provided with two bores 52 for the reception of primer caps 54. Inside the sleeve 46 I position a retaining collar 56 having a bore 56 loosely receiving the head '60 of a rlng pin assembly 62 having pins 64 adapted to bedriven into the primer caps 54 for firing the latter.

Head -60 terminates in a taper 66 lying adjacent a corresponding taper 66 in' the collar 56, and the collar includes a bore 10 lloosely receiving the shank 12 of the iiring pin assembly. Normally the ilrlng pin assembly 62 is held out oi' tiring engagement with the primer cap 54 through the medium of a shear pin 14. A short tube 'I6 has its llower end threaded into the bore 42 and is provided with a threaded neck 16 for connection with tubing 60 through thev medium of a coupling member 82. i

yIn operation, the gun III may be lowered into the well through the medium of a tubing 60. When the gun has been properly positioned, it is red through the medium of a go-devil 64 which is dropped into the tubing for striking- 4the shank 12 to shear the pin 14 and drive the';flr ing pins 64 into the primer caps 54. Go-devilf6'4 is provided with a leading tapered nose 66 to facilitate penetration of discs 66 welded inside a perforated section 96 in the tubingv6ii. The gun is positioned in the well at the topvof the liner or screen associated with the casingfor finside the liner or screen. As the explosionoccurs, the projectile I8 is fired from the guwhlch causes the fluid in the well to be convertedlilritba projectile, and the fluid is driven downwardly vandl outwardly of the screen or liner with suchjforce as to effectively clear all the openings ofithcscreen or liner. The uid is forced throught'he l the nose of the projectile extends. A clamp ring 55 screen or liner and penetrates into the formation in all directions, thus altering the sands and breaking down other obstructions s as to permit a free ow of fluid or gas into the bore hole for recovery through conventional production methods.

'I'he ldiscs 88, before being perforated by the go-devil 84, seal the perforated section 90 from the remainder of the tubing 80 as well as the tube 16. Thus the gun is effectively sealed at its upper end. Perforation of the discs ,88, particularly the upper disc, permits the uid to rush into and upwardly of the tubing 80 which places a vacuum on the sands or other formation to increase the productivity of the Well. Thus the gun as well as the tubing 80 may be left in place after firing so that the tubing 80may be utilized for production purposes. Go-devil 84 is provided with a spiral groove 92 which facilitates passage of the fluid between the go-devil and the tubing.

Firing of the explosive in the chamber I4 will cause the projectile I8 to rupture the washers 30, 32 and 34, but before such rupture, these washers in connection with the sealing plate 26 effectively seal the powder chamber against the entrance of moisture.

My invention completely eliminates the necessity of removing screens and liners for cleaning purposes. Attempts have been made to run tools into such liners and screens but such tools have frequently cut and otherwise damaged the screens and liners so as to necessitate substitutes of liners and screens which entail considerable labor and expense.

In Figure 4 I illustrate a different mechanism for lowering the gun into the well. The gun body I2 is identical with that illustrated in Fig- Aure 2, which is also true of the fixing pin assembly 62. Sleeve 94 differs from the sleeve 46 in that it is devoid of threads, but the collar 56 and the shear pin 98 remain the same. A coupling element 98 is threaded into the bore |00 which corresponds to the bore 42 and the inner end of the coupling member engages the collars 56 and 94 for holding the latter in place.

Coupling member 98 is provided with an enlarged bore |02 for .accommodation of the shank '|2, and the member is Ibored at |04 for the reception of a cable or rope |06 having a connecting element |08 disposed in the enlargement 0 of the bore |04. Member 98 is also provided with .two bores ||2 for the reception of rods ||4 normally held in position of Figure 4 through the medium of frangiblewelds IIB. The upper ends of the rods are fixedly related to a ring ||8 through which the rope or cable |06 passes. A go-devil in the nature of a heavy tubular element |20 is guided downwardly by the rope or cable for striking the ring I I8, to break the welds I8 and drive the rods ||4 onto the firing pin assembly 62. Thus the rods ||4 are driven against the firing pin assembly to shear the pin 96, which in turn fires the primer caps 54. Welds ||6 provide a seal, which is also true of the metallic coupling element |08.

Having thus described certain embodiments oi' my invention in detail, it is, of course, understood that I do not,desire to limit the scope thereof to the exact detailsset forth except insofar as those details may be dened in the appended claim.

What is claimed is:

A gun of the type described adapted to be lowered into a perforated liner comprising a body having a longitudinal bore constituting an explo'- sion chamber, said bore extending through the lower end of the body, a closure means for the lower end of said bore, a ring bore communieating with said explosion chamber, explosive material in said firing bore and said explosion chamber. means for firing the explosive adjacent said firing bore for firing the explosive in said explosion bore to rupture said closure means and direct the forces of explosion into the uid adjacent said liner for removing accumulations thereon, said firing means including a plurality of primer caps and impact responsive firing pins for firing the caps, a tubular member for lowering the gun, including a perforated section in the tubular member, sealing discs inside said perforated section for sealing the tubular member and said gun, and a go-devil for rupturing said discs and for striking said firing pins, said perforated section constituting an inlet for fluid after rupturing of at least one of said discs to permit the fluid to rise in said tubular member.`

CLARENCE A. RICOU. 

